Method of and apparatus for measuring gas



Feb. 27, 1923. 1,446,461. C. W. HINNIAN.

METHOD OF AND APPARATUS FOR MEASURING GAS.

FILED JUNE l5|,192|.

raw 4 Patented ideh. 21/", 19211 at that EXEUUTOR 0.? 5513.1?)

V aim VI; HINT-EBAY, DECEASED.

METHQD 01 AND APPARATUS FOR MEASURING GAS,

Application filed .Iune 15,

To aZZ whom it may concern Be it known that I, Ci-Lnnins W. HINMAN, a citizen ot the United States residin li inchester. in the county of llliddiesex nd State of lvlassachusetts,have invented certain new and useful Improvements in Methods oi? and Apparatus tor Measuring this; and I do hereby declare the following; to be a full, clear, and exact description oil the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to a method of and a ppariuus for nieasuri 11g the flow oi a cart The invention particularlyadapted ror measuring the low of illum nating stations where it lS Ii1,2211TlCtUl'Giil quantities tor municipal or industrial such at city gas plants.

The object of the present invention is to provide a novel and improved thud ot nicasin-inn the How ot a gas and iurther to provide an improved construction of apparatus for measuring the flow according; to the present method.

It has heretofore been proposed to me s the flow ot a by the abstraction from the gas by means of a current or licpiid during the passing of the through a chamberv The incoming and outgoing fluid liquid and gas were both maintained at a constant and invariable temperature so that the flow of the liquid was a direct measure oi the flow oi the gas. T he present methoih however. diiiers :[trom the toreg'i'iinp; method in that the incoming and outgoing; gas and fluid are not maintained at constant and invariable temperatures but, on the contrarya while the individual gas and fluid tempera tures may vary yet a constant temperature difference is maintained between the incoiuing and outginp; fluid and also between the incoii'iing and outgoing as. it not necessar that these temperature differences should be identical.

The invention therefore consists in the method and apparatus hereinatter described and claimed.

The principle underlying. the present method of measuring" the how of a de pends upon the tact that, assumingiithe contact chamber to be well. insulated the heatgiven up by the equals the her-t gained by the water. Assuming A to be the weight oi gg as. B its specific heat C the temperature 1921. Serial No. 477,844..

difference between the, gas at the inlet and outlet of the contact chamber, D the weight oi the Water or other fluid, E its specific heat, and the temperature difference between the water at the inlet and outlet of the chamber then AB C DEF DEF D is determined by reading the Water meter, B and E, the specific heats, being known. and the temperature (litl'erences U and i are, according to the present method and by the present apparatus, each automatically maintained at a predetermined amount it therefore tollows that the gas flow is directly piwuiort-ional to the flow oil the water. In the accompanying drawings, illustrating the preferred embodimentof the invent on, the apparatus for measuring" the gas tiow according to the present method, and by which the predetermined temperature differences between the gas and water respectively at the inlet and outlet oi' the con tact chamber are automatically maintained constant, is shown diagrammatically.

Referring; to the drawings, the contact chamber 1 is provided with a gas inlet 2 and a gas outlet The heat extractingliuu ih pit-eterably water, is caused to flow through a pipe within the contact chamber l and in a direction counter-current to the flow of the gas. The pipe 4 is or may be ffOlIIlGCl in coils of suflicient number to insure that the temperature ditterences of gas and water are constant at any and all rates of flow oi? Water is supplied to the pipe 4 from a supply pipe 7. the flow being controlled by a valve 8 preferably of the well-known balanced type. The flow of the water is. measured by a water meter 12 oi any usual or preferred construction. The gas before entering the contact chamber 1 through the gas inlet v2. is caused to pass through a coolinpichamber Set which may comprise a multi-tubular condenser ot'. the ordinary construction. Water is supplied to the cooling chamber 34; through a pipe 36 the flow being controlled by a balanced valve of ordinary or preferred construction. Provision is made for automatically maintaining a constant temperature difference between the temperature of the gas at the inlet and outlet of the contact chamber. Fortl is purpose thermostats 1:0, 12 of equal volume are located .in the contact chamber at the inlet and outlet ends; thereof respectively. Battle plates 43, 1-4: are provided to deflect the gas in a direction lengthwise of the thermostats. .he thermostats 10 4&2 are provided with pipes i5, i6 connecting; the thermostats with mechanisn'i indicated by the generalreference l? for actuating thewater valve 35 controlling; the flow oi water to the cooling chamber 34.

The flow of water through the supply pipe '7 and the coils at within the contact cham ber controlled by mechanism indicated by the general reference 50 for actuating; the water valve 8. The water entering and leaving the coil pipe 4: within the contact cl'iamber is caused to flow through thermostats 52, 5a of equal volume each operatively connected by pipes 56, 58 "to the mechanism 50. i l

The mechanisms 1? and 50 are similar in construction. T he mechanism 4-1;? comprises four cylinders 60, 61, 62, 63 arranged one above the other, as shown in the drawing. The upper cylinders 60, 61 are rigidly connected together, being guided in suitable supports (not shownlso as to be free to move vertically. The upper cylinders 60 and 61 are closed at their upper ends and are open at their lower ends. A. piston 65 slideswithin the cylinder 60 and is rigidly supported in a stationary position by a connector 66 secured to a fixed bracket 67. A piston 70 slides within the cylinder 61 and is provided with a depending stem 7 1. The cylinder 62 is open at both ends and three pistons 78, 79 and! 80 slide within the cylinder 62 and are themselves secured upon the depending stem 7 1- to move therewith. The lower cylinder 63 is closed at both ends, and a piston 81 sliding within the cylinder is provided with a stem 82 carrying upon its lower end the movable portion of the valve 35 so that movements of the piston 81 operate to directly control the flow of water from the supply pipe '7' through the pipe 36 to the coolingchamber The cylinders 62 and 63 arepconnected by by-passes 83 and 3-1- arranged as showm the by-pass 83 leadin; to the top of the cylinder 63 above the piston 81 and the by-pass 8 1 leading to below the piston 81. The water inlet 80 leading;

to the cylinder 62 is controlled by the piston 79 and] the water outlets 86 and 87 are controlled by the pistons 78 and 80. The mechanism indicated by the general reference 50 for controllingthe actuation of the water valve 8 is of the same construction the mechanism 17 just described and includes cylinders 160, 161, 162 and 163 having the pistons 165, 170. 178, 179, 180 and 181 connected in a similar manner by the parts 166,

167, 175, 17-1 and 182 to the movable portion. of the water valve 8. The cylinders 162 and 163 are connected in exactly thesame manner by by-passes 183, 184, and the cylinder 162 is provided with the water inlet 185 and the water outlets 186 and 18?.

From the foregoing description oi the construction ot the mechanisms 1? and 50 it will be apparent that because the cylinders 60, 61 and 160 and 161 are capable of movement witn relation to their pistonsthat wheiithe temperatures at the inletand outlot of the Contact chamber ri.seequally so as to maintain a constant diilerence in temperature between the gas at these two points, the timid witl in thethern'iostats 10 and 4:2 expandsequally and; causes merely the raisinc; of the cylinders 60 61 without causing a (hag'n'ession of the piston 70 and water coin trolling valve 79 which moves therewith. tiiimilarlyrit the difference intemperature between the inlet and outlet water flowing thro th the coil pipe at withinthe contact chamber remains constant, or in other words it the temperatures thethermostats andlii rise equally, expansion of the thud within thetherniostats '52 and 5a operates merely to cause the cylinders 160 and l6l to rise with relation to their pistons without causing depression of the piston 170 and piston 11 9 which controls the water flow from the pipe 185 and is normally moved with the piston 170. It is only when this dir'l erence in temperature between either the inlet and outlet water flowing); through the pipe 4; or between the inlet and outlet gas tlowiiug through the contact chamber varies from a constant hat movement of the pistons TO and 170 occursso as to alter the flow ot water through the alves and 8 respectively. y

The operation of the aru'iaratus may be described follows: nssuniing that the to peratnre differences betweenthe gas at the inlet and outlet of the contact chamber and the water at the same points are maintained constant. the flow ot the gas through the contact chamber is directly proportional to the How of the water so that calibration of the water meter .2 enables the flow of the. gas to be read directly in units or" volume fas for example in cubic feet. As the rate of how of the gas through the con tact chamber increases or decreases the rate 0t flow of the water is propertionately increased or decreasedin a manner as will be described. so that the reading of the water meter 12 affords a true measure of the quantity of gas flowing through the con tact chamber. 7

Assuming that a gas has specific heat of .0231 it is a tact that three gallons of water flowing through the water meter 12 raised 12 degrees are required to cool one thousand cubic feet of 13 degrees. Assuming that ill) ltlu

intone 1 the gas from thepurifiers in the ordinary manufacture of illuminating gas in the amount of one thousand cubic feet enters the cooling chamber 34 at a temperature of for example 90 degrees it is cooled some what toa temperature of 83 degrees, so that the temperature ot the gas entering the contact chamber 1 is 8?; degrees. ilissuming that three gallons of water flowing'through the Water meter" enters through the therurostat 52 at 5'? degrees and are caused to flow through the coil pipes in a direction counter current to the flow of the gas. and that the gas is cooled degrees so that it leaves the contact chamber at a temperature oi? 70 degrees at thesame time the water will be raised in temperature 12 degrees so that it leaves through the thermostat 34 at 69 degrees. The operation of the mechanisms l? and in mainta ining a' constant difference of temperature between the inlet and outlet wateraind the inlet and outlet may be best described by considering their operation; when the temperature of the gas itself increases and then by considering their ope 'ation when the tempo 'ature ot the water increases.

Assuming that the general conditions remain normal and that the temperature of the gas entering the cooling chamber is 95 degrees instead of 90, in passingtl'irough the cooling chamber the gas will be cooled alittle more than under normal conditions because of the greater difference in temper" ture bet-ween the coolingwater and the gas so that it enters the contact chamber at a temperature as for example 86 degrees. In passing" the thermostats 40 the gasat the increased temperature causes the expansion or the thermostaticllui d depressing the piston 70 within the cylinder 61, lowering the piston 79 within the cylinder 62, and permitting Water to flow 'liroin the supply pipe '7 through the pipe 85=towithin the cylinder 32 above the piston 79, thence through the bypass 83 to the cylinder 68 above the piston 81 thus operating to depress the latter and to open the valve 35 to increase the Flow ol cooling water to the chamber This permits the flow of sufficient additional water to the cooling chamber 34: to reduce the temperature of the gas passing" therethrough so that as the enters the gas inlet 2', it has been cooled to its normal temperature of For example 83 degrees. During the cooling of the gas the thermostatic fluid within the thermostat 4L0 contracts to its original or normal temperature thus permitting the air pressure upon the bottom (it the piston 70 to cause it to rise and to thereby shut ofi the flow of water from the pipe 85 by the piston 7 9. However, the gas before it has been cooled to normal, while passing through the contact chamber at a temperature of 86 degrees will cause the temperature of the water as it leaves the contact chamber and flows through the thermostat 54: to rise to say for exan'iple '72 degrees (the normal outlet temperature being 9 degrees). This increase in the temperature of the outlet water within the thermostat operates to expand the fluid in the thermostat 54 thereby operating to depress the pistons 170 and 179, permitting the flow of Water from the pipe 185 through the b ypass 183 to above the piston 181 Within the cylinder 163, thus depressing the valve 8 and permitting an increased flow of Water through the coil pipe l. The increased flow oil water continues until the temperature 01 the water leaving the coil pipes through the thermostat 54 has returned to a normal value of 69 degrees. During the reduction oi the temperature of the water from 72 degrees to 69 degrees. the thermostati uid contracts to its original volume pernr ting the air pressure upon the underside oi the piston 170 to cause the flow of water from the pipe 185 to be shut oil by the pi. cu 179. The foregoing cycle of operations takes place whenever the temperature of the gas in creases. It is obvious that a reverse cycle of operations would take place should the temperature oi the gas decrease below its normal value. In such an instance the thermostatic fluid within the thermostats 4L0 and 5 1 would contract permitting the air pressure upon thepistons and 170 to cause the operation of the valves and S to diminish the flow of Water to the cooE-i chamber 34k and coil pipes 4: respective It will therefore be observed that in the event of either an increase or decrease in the gas temperature the mechanisms l7 and 5t) operate in the foregoing manner to auto matic-ally maintain a constantdiilerencc in temperature between the inlet and outlet gas and water respectively.

Assuming that all conditi is remain normal with the exception that the temper ture of the water supply increases. as for example 5 degrees. so that instead oi? entering through the thermostat to the coil pipes 4: at a teu'iperature of 57 degrees it enters at a temperature of 62 degrees in such an instance the thermostatic fluid within thrthermostat 52 will expand. forcing up the movable cylinders 160 and 161' with-rela tion to the fined piston 165 and lined support 167. The upward movment ot the cylinder 160 draws up the piston 1'50 and also the piston 179 allowing water to-enter beneath the piston 179 from the pipe 185 and thence to pass through the by-pass 184: to below the piston 18.1 and to thereby decrease the flov'v of water through the valve 8. In consequence of the decreased flow of water through the coil pipe Ar. and also be cause of the increased temperature of the water, the outgoing water flowing through the thermostat 54 reaches a relatively high temperature, as for example 79 degrees. The increase in temperature (10 degrees) within the thermostat 5i operates through the expansion of the thermoi-jitatic fluid to depress the pistons 170 and 179 with relation to the cylinder 160 an amount twice great as the increase in the temperature ot the waten namely 5 degrees (from 57 do grees to 62 degrees) caused the cylinder 180 to rise. This depression of the piston 179 permits water to flow from the pipe to the by-pass 183 to above the piston 181 thus operating to increase the rate oli .t'l-ow oi? water through the valve 8. The increased flow of water continues until the temperature within the thermostat has dropped 5 degrees to approximately '74 degrees at which time the contraction of the thermostatic fluid will have permitted air pressure upon the underside of the piston 170 to return the parts to their normal position in which the water in the pipe 185 is cut of? by the piston 17 9. The mechanism 50 therefore operates to maintain the temperature of the outgoing water at the thermostat 541 at 74: degrees. Meanwhile, however, the temperature of the outgoing gas in contact with the thermostat 12 within the contact chamber has increased from degrees (its normal value) to 7 5 degrees. This increase in temperature forces up the cylinder 60 through the expansion of the thermostatic fluid within the thermostat 42. As the cylinder 6O rises it carries with it the pistons 70, 79, thus operating to lift the piston 81 and cut down the flow of water to the cool-- ing chamber 34% by closing the valve 35. The decreased flow or" water to the cooling chamber 34 operates to permit the temperature of the inlet gas to rise and as it rises the thermostatic fluid is caused to expand thus operating to depress the pistons 70 and 7 9 until the water supply from the pipe 85 has been cut off by the piston 79. The apparatus is adjusted so that the piston 7 9 is in a position to shut off the flow of water from the pipe 85 when the temperature'of the inlet has reached 88 degrees, thus maintaining a difference in temperature be tween the inlet and out-let gas of 88' degrees75 degrees. oru13 degrees. As above described the cooling water entering the coil pipes 1 at a temperature of 62 degrees was automatically maintained by the mechanism 50 to an exit temperature of 74 degrees, thus maintaining a constant difference of 12 degrees between the inlet and outlet water. It will therefore be observed that in the event that the temperature of the water supply increases the apparatus automatically maintains a constant difl erence in temperature between both the inlet and outlet water and gas.

It is obvious that should the temperaturev and 165 respectively.

of the supply of water decrease instead of increase, the foregoing cycle or operations will be reversed, the airpressure operating to cause upward movement. oi the pistons 160 and 170 upon the contraction of the thermostatic fluid within the pipes 56 and 58. The efiect of the air pressure may if desired be supplemented by a counter weight or spring (not shown).

As the quantity of gas passing through the contact chamber increases or decreases. the temperature difierences of the water and gas being as above described maintained constant, the apparatus will operate to automatically increase or decrease the flow oi" water through the coil pipes l and theretorc through the water meter 12, so that the reading of the water meter 12 will be directly proportional to the quantity of passing through the contact chamber. It the flow of gas is thus increased the temperature of the outlet water passing through the thermostat 54 increases, because the same amount of water at the same temperature as before is used to cool an increased amount of gas the same number oi? degrees as before. The area of the surface of the coil pipes 4 is sufficiently great to insure suflieient transfer of heat from the gas to the water so that the valve 8 will be opened through the depression of the pistons 170 and'179 upon the expansion of the thermostatic fiuid within the thermostat 54:.

lnorder to adjust the relative position of the cylinders" 60, 61, 160, 161.,with their pistons 65, 70, 1.65, 170 respectively, provision is made for selectively introducing variable quantities of thermostatic fluicbfrom a source of supply through a pump 120 connected to the pipes 45, 46, 56 and .58 respectively. Suitable valves 122 are provided for permitting the selective introduction oi the thermostatic fluid from the pump 120 to any one of the cylinders.

Each of the mechanisms 47 and 50 is pro vided with an index 172 carried by a supporting rod 175 secured at its upper end to the fixed clamps 67 and 167 respectively. In this manner the indexes are maintained at a definite distance from the pistons 65 By reading the index with relation to the position ofa mark upon the stems T4 and 17 1-. the operator can ascertain whether the apparatus is at any time in its condition oi initial adjustment. As the temperature of the water and gas rises and falls with the dilierent seasons of the year the amount of fluid within each of the cylinders 60, 61, 160 and 161 may be varied. by adding more fluid or removing fluid from the cylinders. By clamping the indexes by the set screws 173 to the stems 7 i and'ii' lirespectively both sets of pistons 60 and 70 a'nd160 and 170 are rigidly secured together so that the same amount of invention has been illustrated and described, it is to be understood that the same may be embodied n other forms within the scope of the following claims.

Having thus described the invention what is claimed is:

l. The method of measuring the flow of a gas which consists in abstracting heat from the gas by means of a current oi? fluid. measuring the flow of the fluid and mar t: ning constant '(Tlli'l QX'GY CQS between the temperature of the fluid before and after action upon the gas and between the temperature oi the before and after action upon the fluid, said temperature differences being maintainedirrespective of the individual temperatures of the fluid and gas before their action upon one another.

2. An apparatus for use in measuring the flow of a having, in combination, means for abstracting heat from a current of gas by a current of fluid, means for measuring the flow of the fluid and thermostatically operated mechanism for maintaining constant diflerenccs between the temperatures oi the fluid before and a; LQl' action upon the gas, and thermostatically operated mechanism for maintaining constant, differences between the temperatures of the gas before and after action upon the fluid, said mechanisms having provisions for maintaining said temperature differences irrespectim 7, the individual temperatures of the fluid and gas before their action upon one an other.

3. An apparatus for use in measuring the flow of a gas having, in combination, a chamber through which the gas to be meusured is passed, means for passing a confined current of fluid through the chamber to abstract heat from the gas, means for measuring the flow ot' the fluid, and thermostatically operated mechanisms for respectively maintaining constant differences between the temperatures of the fluid before and after action upon the gas and between the temperatures of the gas before and after action upon the fluid said mechanisms having provisions for maintaining said temperature differences irrespective of the individual temperatures of the fluid and gas before their action upon one another, said thermostatically operated mechanism i11- eludin a air of connected c linders hiss P .V i

tons within the cylinders adapted to be moved in one direction under the influence oi. a thermostatic fluid, and means for selectively introducing varying quantities of thermostatic fluid to the cylinders to vary the position of the pistons with relation to the cylinders, said thermostatically operated mechanism having provision whereby one set of pistons are moved with relation to the cylinders only when the temperature differences between the fluid and gas before and after action upon one another vary from predetermined values.

An apparatus for use in measuring the flow of a having, in combination, a chamber through which the gas is to be passed, means for passing a confined cur rent or"? fluid through the chamber to ab stract heat from the gas, means for measuring the flow ott rhe fluid, a fluid control. chamber for pre-cooling the gas before its passage through the main chamber, valves controlling the flow of fluid to both chamhers, and mechanisms for respectively maintaining constant ditl'erences between the temperatures of the fluid before and after action upon the gas and between the temperatures of the gas before and after action upon the fluid. including thermostats arranged to be acted upon by the entering and leaving the chamber, thermostats arranged to be acted upon by the heat abstracting fluid. as it enters and leaves the chamber, two sets of movable cylinders opcrative-ly connected with the and fluid thermostats, pistons within the cylinders. connections between one set of pistons and the fluid control valves, said cylinders being arranged to be moved with relation to said latter set 01 pistons only when the temperature differences between the fluid and gas before and after action upon one another vary trom a predetermined value.

5. An apparatus for use in measuring the flow of a gas having, in combination, means for abstracting heat from a current of gas by a current oi fluid, means for measuring the flow of the fluid, and n'iechanisms for respectively maintaining constant diflerences between the temperatures of the fluid before and after action upon the gas, and between the temperatures of the gas before and after action upon the fluid, said mech anisms having provisions for maintaining said temperature diflerences irrespective of the individual temperatures of the fluid and gas before their action upon one another.

CHARLES W. HINMAN. 

